1. Field
One or more embodiments herein relate to an air conditioning system.
2. Background
An air conditioning system generally includes an indoor unit and an outdoor unit, which are driven to cool and heat one or more areas according to a user's request. The indoor unit and the outdoor unit are typically connected to each other through a refrigerant pipe.
Recently, a multi-air conditioning system has been developed to include a plurality of multi-air conditioners having an outdoor unit for controlling distribution and circulation of a refrigerant, indoor units for discharging air to each chamber by being commonly connected to the outdoor unit, and a controller for controlling the multi-air conditioners by connecting the multi-air conditioners to one another.
For instance, as shown in FIG. 1, an air conditioning system includes one outdoor unit 200, and a plurality of indoor units 100A-100D connected to the outdoor unit 200 through a refrigerant pipe 300.
Such an air conditioning system circulates a refrigerant, an operation fluid, in the order of a compressor, a condenser, an expansion valve and an evaporator, or in a reverse order, thereby heating or cooling an indoor chamber. This refrigerant is filled in the air conditioning system by a predetermined amount according to a capacity of the air conditioning system when installing the air conditioning system.
However, as the air conditioning system is continuously used, the refrigerant is consumed to become deficient. This may degrade efficiency of the air conditioning system. Accordingly, a new refrigerant has to be supplemented. To this end, have been developed techniques for constantly maintaining a refrigerant amount by filling a refrigerant into an air conditioning system according to a capacity of the air conditioning system.
The refrigerant pipe which connects the outdoor unit and the indoor unit to each other is installed in a building in advance. As the number of the outdoor units and indoor units is increased or as a distance between the outdoor unit and the indoor unit(s) becomes long, the refrigerant pipe must also be increased in length.
The air conditioning system has a different pipe length and a different amount of refrigerants to be filled according to an installation environment. This may cause a difficulty in properly maintaining a refrigerant amount.
Furthermore, when directly applying the conventional technique for filling refrigerants to an air conditioning system to a recent multi-air conditioning system, an error may occur in calculating a refrigerant amount according to installation conditions such as a pipe length, etc.
Furthermore, when determining a refrigerant amount by measuring a temperature and a pressure in the conventional art, a larger number of temperature sensors or pressure sensors have to be installed as a pipe length is increased. This may cause high costs, and may degrade reliability when measuring a smaller number of sensors.
One of the conventional methods for calculating a refrigerant amount is to determine whether a refrigerant amount is proper or not by filling an additional refrigerant amount in an air conditioning system, and then by driving the air conditioning system. In this case, since whether a refrigerant amount is proper or not is determined after filling an additional refrigerant amount in an air conditioning system, an installation time of the air conditioning system is increased.
Furthermore, since an additional refrigerant amount is directly calculated by a user, the user's convenience may be lowered. Also, a refrigerant amount may be wasted, and a refrigerant amount error may occur according to a user's capability.